Antimicrobial effects of silver/copper/titanium dioxide-nanocomposites synthesised by chemical reduction method to increase the shelf life of caviar (Huso huso)

This paper focuses on the use of incorporation of silver (Ag) and copper (Cu) nanoparticles in titanium dioxide (TiO2) nanocomposites, as Ag/Cu/TiO2 nanocomposite was synthetized through the chemical reduction method against food borne microorganisms. The antimicrobial effect of Ag/Cu/Tio2 nanocomposite demonstrated a considerable antimicrobial activity as order as Escherichia coli > Staphylococcus aureus > Aspergillus niger. The results of the agar diffusion test exhibited no halo growth around the discs of four nanocomposite samples, which indicated the perfect inhibitory effect of synthesized Ag/Cu/TiO2 nanocomposites against the afore-mentioned bacteria. Scanning electron microscopy (SEM) analysis exhibited that Ag and Cu nanoparticles were homogeneously distributed into the TiO2 nanocomposite. Furthermore, the results of inductive coupled plasma mass spectrometry (ICP-MS) method showed that 0/168 ppm of Ag was released to caviar samples on 32nd day and 62nd days of the experiment. All findings indicated that the combined usage of Ag/Cu/Tio2 nanoparticles could meet all desirable objectives including increase of antimicrobial activity and reduction release of Ag nanoparticles into the caviar, which extends caviar shelf life.